Weevils - Entomological Society of Canada

Description. Length 12-18 mm. Body elongate oblong, robust,
black, shining. Pubescence sparse; setae prostrate, ash gray and pale
brown; gray setae forming 1 narrow median and 2 wider lateral stripes
on pronotum and 1 narrow pale stripe along every second elytral
interstriae; interstrial gray strips broken by 3 or 4 small rounded tufts of
black hairs. Scutellum white. Head and rostrum together slightly longer
than pronotum. Rostrum carinate along middle; surface densely
rugose-punctate. Pronotum subcylindrical, about as long as wide; apex
and base truncate; sides weakly arcuate; disc densely rugose-punctate.
Elytra at base nearly twice as wide as pronotum; sides parallel for
four-fifths of length, then suddenly converging to obtuse apex; striae
indistinct, coarsely punctured; interstriae weakly convex, densely
rugose. Abdomen in male with last visible ventral tergite strongly
convex, visible from beneath. Pygidium deeply grooved in both sexes,
projecting slightly beyond elytra.
Distribution. Ontario and Quebec, south through the eastern
United States to Texas and Georgia, west to Wisconsin and Nebraska,
Ontario: Grand Bend, Jockvale, Marmora, Merivale, Ojibway, Parkhill,
Prince Edward County, Simcoe, Strathroy, and Walsingham. Quebec:
Beech Grove, Lac Bernard, Montreal, Old Chelsea, and Saint-Hilaire.
Comments. This species is commonly known as the New York
weevil. It is occasionally a serious pest in orchards. Sanborne (1981)
reports two distinct color forms in three separate geographical areas. A
northern gray form occurs throughout northeastern United States and
southern Canada; in this form, little contrast is found between the light
and dark patches of pubescence. Two southern melanic forms, which
occur primarily in the southeastern United States, have highly
contrasting light and dark patches of pubescence. Structural differences
among the three populations suggest that these forms are discrete
geographical populations that could be given subspecies status. More
study is required, especially of the southern forms, before such a
distinction is made. Larvae feed on roots of American hornbeam
(Carpinus cq.roliniana), gray birch (Betula populifolio), butternut
(Juglans cinerea), butternut hickory (Carya cordiformis), shagbark
hickory (C. ouata), American beech (Fagus grandifolia), American
chestnut (Castq.neq. dentata), and oak (Quercus species). Adults are
occasionally taken on cultivated fruit trees such as apple, plum, and
peach. Adults feed on the new season's growth of shoots, leaf petioles,
leaf buds, and acorn buds. The females lay eggs in the summer in small
depressions in the soil around the bases of trees or saplings or other
vegetation. Larvae develop on the roots ofthe host plants by feeding on
the vascular cambium and phloem. They completely remove the outer
bark. The larvae feed primarily on the lower surfaces of lateral roots.
The insects spend most of the summer and subsequent year in the larval
stage. Pupation occurs in May or June of the second year, and adults
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